On Sat, Jun 25, 2011 at 8:18 AM, Tim Berners-Lee <timbl@w3.org> wrote:
>
> On 2011-06 -24, at 22:24, Xiaoshu Wang wrote:
>>> Can I use that URI for statements about a picture?
>>> Can I use that URI for statements about Barak Obama?
>>> for example.
>>
>> Yes, either way is fine.
>
>
> In that case, your proposed system is not the WWW, and not the Semantic Web.
> It is a different imaginary system, which you are free to develop, but you should not use the term "HTTP".
>
> In the Semantic Web, Â I can say
> Â Â Â Â <ex:i> Â <fb:like> Â Â <http://www.knox.edu/Images/_News/news_media/img/2005/obama-barack-1ss.jpg>.
>
> and it unambiguously means that I like the image, not the person.
> This is very valuable.
It would be valuable if it were true, but it is not. Firstly, using
the same argumentation style that Jonathan employed in response
another of Xiaoshu's emails, you have not unambiguously defined ex:i
or fb:like and they could mean absolutely anything.
Secondly what resource is denoted by the knox.edu URI? I content there
are several possibilities:
a) the person called "Barack Obama". Perhaps further RDF statements
might say that resource is wearing a tie.
b) the photograph of that person as originally taken by the camera.
Further RDF statements might say who the creator of that photograph
was, or talk about the lighting used or the composition.
c) the digital version of that photograph, perhaps scanned. Further
RDF statements might say the digitisation process or resolution.
d) the file format of that digital image. Further RDF statements might
state the compression factor, or refer to the EXIF data that JPEGs can
have.
I think your statement is referring to d) but its' certainly ambiguous
in that sense. It can be disambiguated by publishing more data about
that URI.
If you think I am wrong, then please tell me what this statement means:
<ex:i> <fb:like> <http://128.252.39.97/SnapshotJPEG>.
Ian